Numerous industrial fields have recourse to polymer materials for creating their products, such as plastics materials. In the present context of recycling waste, there is therefore a need for recycling industrial waste and in particular polymer waste.
It is thus known to recycle such waste by subjecting it to various chemical and/or heat treatments.
For example, a heat treatment device is known that comprises an enclosure, means for conveying the substance between the inlet of the enclosure and the outlet of the enclosure, which means comprise a screw mounted to rotate inside the enclosure about an axis of rotation, and means for driving the screw in rotation. The device also has heater means for heating the screw by the Joule effect.
Waste is usually inserted in the inlet of the enclosure in the form of divided solids that are raw or of divided solids that have been preconditioned, e.g. by a densification step.
The screw pushes the granules continuously towards the outlet of the enclosure. Because of the temperature of the screw, the granules soften progressively inside the enclosure until they melt. The granules as melted in this way can then be prepared in order to be reused, thus enabling treated waste to be recycled.
Nevertheless, such devices are not adapted to treating certain materials. In particular, certain kinds of plastics material waste reach their melting temperature very slowly and therefore melt only belatedly after entering into the enclosure.